Effect pigments, also known as gloss or lustrous pigments, are well known as pigments which produce unique coloristic effects. The optical properties of effect pigments are governed by reflection and/or interference phenomenon. In particular, finishes containing an effect pigment produce a "flop effect" whereby the coloristic characteristics of the finish change depending on the viewing angle. In general, when a change in viewing angle results in a change in lightness, the effect is referred to as "lightness flop", and when the change is in hue, the effect is referred to as "color flop".
Due to their unique color characteristics, the market for effect pigments is growing in such uses as cosmetics, inks, plastics and paints, especially automotive paints. Weatherfast effect pigments are currently employed in large quantities in the automotive paint industry.
This invention relates to the surprising discovery that thin film finishes with new styling effects are prepared using a coating composition containing a small particle size filler having a porous surface, such as a ultrafine polyamide powder, in addition to an effect-producing amount of an effect pigment; especially when the small particle size filler is incorporated into the coating composition as a component of a pigment composition which also contains a colored pigment. In particular, such coating compositions produce finishes which possess a high lightness and color flop, as well as a profound color deepness, resulting in a three-dimensional appearance.